The Paccar MX-13 Injector Lawsuit Moves Forward. What Engine Failures Mean for Your Truck Insurance
A federal judge just let owners of Kenworth and Peterbilt trucks with 2021 MX-13 engines take Paccar to court over failing fuel injectors. Here is what that fight means for owner-operators, and where your insurance does and does not step in.
What happened with the MX-13 lawsuit
On October 13, 2026, Land Line reported that a warranty lawsuit over Paccar's EPA 2021 MX-13 engine is going forward. In an October 1 order, U.S. District Judge Robert S. Lasnik rejected Paccar's argument that the Clean Air Act blocked the claim, which means the truck owners do not have to prove the engines broke federal emission rules to keep their case alive. The ruling does not decide who is right and it does not certify a class. It simply lets the case move ahead.
The proposed class action was brought by 30 companies and one individual who run Kenworth and Peterbilt trucks with this engine. They say deposits build up inside the fuel injectors and throw off fuel delivery, which shows up as knocking, hard vibration and sudden power loss. Paccar denies breaking its warranty and says it handled the injector repairs and replacements at no cost to the owners. The owners say those repairs kept failing.
The real cost is the downtime
The numbers in the complaint, as Land Line described them, show what a recurring engine problem does to a small operation. One Kansas carrier says its trouble started just past 1,000 miles and that it logged eight fuel system incidents by roughly 206,600 miles. A Missouri carrier reported 19 repair visits and 110 days of downtime across five trucks. A Michigan hauler says the breakdowns left it unable to keep up with its payments, and it surrendered its trucks to Paccar Financial.
Notice what the owners are actually fighting about. The warranty paid for parts and labor. What it excluded was downtime, lost income and other consequential damages, and the plaintiffs are arguing those exclusions should not hold up because the repairs did not work. In other words, the shop bill was never the expensive part. The parked truck was.
Why your truck insurance will not pay for this
This is where a lot of owner-operators get surprised. Physical damage coverage pays when your truck is damaged by a covered event, such as a collision, fire, theft or a storm. It does not pay for an engine that wears out or fails on its own. Mechanical and electrical breakdown is a standard exclusion, so a bad injector, a failed turbo or a fuel system that keeps derating is a warranty and maintenance problem, not an insurance claim.
The same goes for the income you lose while the truck sits. A standard truck policy is built to pay for damage and liability, not for the loads you could not haul. We broke down that gap in detail in our guide on why physical damage coverage does not cover downtime, and the MX-13 case is a real world example of exactly that problem.
Where insurance does come in
Sudden power loss is not only a repair headache. If an engine derates on a busy interstate or in a merge lane and someone runs into you, that is a liability event, and your commercial auto liability policy is what answers for the other driver's damages. After a crash like that, a plaintiff attorney will ask whether you knew the truck had a history of power loss and what you did about it. Your repair orders and warranty paperwork become evidence, for you or against you.
Financing is the other pressure point. The Michigan hauler in this case ended up handing trucks back to the lender. If your truck is financed, your lender requires you to keep physical damage coverage in force, and a long stretch without revenue can make it tempting to cut corners on the policy. Letting it lapse can trigger force placed coverage at a far higher price, or default on the loan.
What to do if you run an affected engine
Keep every repair order, every warranty claim number and every note about when the truck derated or lost power. That record helps any warranty fight and it shows an underwriter or a jury that you maintained the truck and acted on known problems. Plan for downtime with a cash reserve or a backup truck, because no standard policy will cover the lost loads. And if repeated breakdowns are squeezing your budget, talk to your agent about deductibles and limits before you think about dropping coverage.
Get a truck insurance quote
A truck that keeps breaking down puts pressure on every other bill, including your premium. Get a truck insurance quote in under a minute through our quick quote form, or call or text 423-264-4255 and talk with someone who works with owner-operators and small fleets every day.
Common questions
Does physical damage insurance cover a failed engine or fuel injectors?
No. Physical damage coverage pays for damage from covered events like a collision, fire or theft. Mechanical breakdown, including fuel injector failure, is a standard exclusion and falls under the manufacturer warranty or your own maintenance budget.
Does truck insurance pay for lost income while my truck is in the shop?
A standard truck insurance policy does not pay for lost loads or income while a truck is down for repairs. That is why the MX-13 owners are fighting the warranty exclusions for downtime and lost income in court instead of filing insurance claims.
Who pays if my engine loses power and I get hit?
If another driver is hurt or their vehicle is damaged, your commercial auto liability policy responds to their claim. Your repair records may be reviewed to show how you handled any known power loss problems, so keep them organized.
How do I get a truck insurance quote if repairs are eating my budget?
Call or text 423-264-4255 or use the quick quote form on our homepage. We can look at deductibles and limits with you to get a truck insurance quote that fits your operation without leaving gaps your lender or the road will punish.
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